This application is a division of co-pending application Ser. No. 895,206, filed Aug. 11, 1986, now U.S. Pat. No. 4 ,818,461, which was a continuation-in-part of application Ser. No. 774,225, filed Sept. 9, 1985 now abandoned.
Beverage service in fast food restaurants, concession stands and other locations where beverages are dispensed, commonly utilizes containers having lids formed of thin plastic material. It is desirable to have a means for opening a portion of such lids so that the beverage can be consumed from the container while at the same time a major portion of the lid remains intact on the container to prevent spillage. Prior art lids of this type have included segments defined by predetermined score lines which were intended to rupture so that the segment could be removed. It has been found that in conventional methods for scoring sheet materials, whether the scored segments be removable or simply bendable, that there are problems in forming the score lines due to destruction of tooling by reason of misalignment of parts or by reason of tears or openings at the score line caused by excessive penetration of the tooling. The later problem has resulted in leaks when the material scored was a lid for a liquid containing cup. A further problem has been found in that sometimes conventional scoring techniques stretch the plastic material and produce so-called "oil can" effects evidenced by unsightly bulges either inwardly or outwardly adjacent the score lines.
A further problem has been the inability of the score lines to reliably provide a path to which the tear line will be contained when removing a segment.
It has been found in accordance with the techniques of this invention that the foregoing problems in the prior art are overcome.